First, what type of repair? How hot do the affected parts really get, must the seal be structurally strong, etc.? Are you referring to degrees in C or F?

Regrettably, all but some high-performance silicone adhesives are not suited for constant use over 400-450F. Sealing heater parts with silicone probably isn't going to work, but sealing parts with hot air flowing through, such as a wand not in contact with the heater, should be no problem.

There are a variety of ceramic adhesives, most either silica/quartz or alumina-based, with service temperatures in the 1000-3000?F+ range, but these are hard to find in tubes or other small quantities at other than incredibly marked-up prices.

Must you use a glue? Can you use a tape, such as common PTFE/Teflon plumber's pipe sealing tape?

First, what type of repair? How hot do the affected parts really get, must the seal be structurally strong, etc.? Are you referring to degrees in C or F?

Regrettably, all but some high-performance silicone adhesives are not suited for constant use over 400-450F. Sealing heater parts with silicone probably isn't going to work, but sealing parts with hot air flowing through, such as a wand not in contact with the heater, should be no problem.

There are a variety of ceramic adhesives, most either silica/quartz or alumina-based, with service temperatures in the 1000-3000?F+ range, but these are hard to find in tubes or other small quantities at other than incredibly marked-up prices.

Must you use a glue? Can you use a tape, such as common PTFE/Teflon plumber's pipe sealing tape?

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thank you so much for posting

basically i need to glue a Da Buddha heater cover together. its broke into 2 pieces and goes back together very well when your holding it... if that makes sense...? not sure if any kind of tape would work. it would be preferable that it could hold the weight of the wand, but if i have to hold the wand that is ok also.

so the heater cover on the DBVs get very hot. i assume upwards of 500 degrees...?

heres a pic of a DBV heater cover and where mine is cracked. the crack goes from the air hole to the bottom on both sides...

so the heater cover on the DBVs get very hot. i assume upwards of 500 degrees...?

heres a pic of a DBV heater cover and where mine is cracked. the crack goes from the air hole to the bottom on both sides

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That glue asking about is acrylic based, just common meltable but probably food grade plastic. Yes, it probably is dishwasher and hot food safe, but will it will probably be vaporizing/boiling at 500?F.

I was taught that chemical laboratory glassware (borosilicate glass) is brittle and once broken the areas all around the break have been (micro)fractured and shouldn't be trusted to handle stress, with adhesive not going to work for any part put under stress, which seems to be the case here. Worst case hazards here include inhaling glass flakes or chips from unsecured pieces and new cracks fracturing. And this does not even consider that this heater output part is going to be highly heat stressed. But I'm sure there are some real glass experts here.

Buy a replacement. You can always use hot spoons or something else jury-rigged for vaporizing.

This Silbond stuff is pretty good - I used it on my pellet stove last winter and it's holding up fine. www.gluehow.com/glues/SilbondRTV
Says it can go up to 500F anf 650F intermittently. It dries red though so if you want something that doesn't show, that site has some food-safe glass to glass recommendations that are clear and might work too.